Automatically pulsing different aspiration levels to an ocular probe

Abstract

Methods and systems for automatically pulsing different aspiration levels to an ocular probe are disclosed. The probe may be a phacoemulsification probe. A first aspiration level, supplied by a first pump, may be applied to the probe simultaneously with ultrasonic energy. A second aspiration level, supplied by a second pump, may be automatically switched from the first aspiration level, and applied to the probe in a pulsed manner.

What is claimed is: 
     
       1. A method for applying aspiration to a probe, the method comprising:
 applying a low flow-rate aspiration from a first pump to an aspiration port of the probe; 
 detecting that the aspiration port of the probe is insufficiently occluded; 
 applying a high flow-rate aspiration from a second pump to the aspiration port of the probe to increase occlusion at the aspiration port of the probe, if the aspiration port of the probe is detected to be insufficiently occluded; 
 reducing the high flow-rate aspiration to match an irrigation flow-rate on a condition that the high flow-rate aspiration exceeds the irrigation flow-rate; 
 not applying ultrasonic energy to the probe, if the aspiration port of the probe is detected to be insufficiently occluded; 
 detecting that the aspiration port of the probe is sufficiently occluded; 
 discontinuing the high flow-rate aspiration and reapplying the low flow-rate aspiration to the aspiration port of the probe, if the aspiration port of the probe is detected to be sufficiently occluded; and 
 applying ultrasonic energy to the probe, if the aspiration port of the probe is detected to be sufficiently occluded. 
 
     
     
       2. The method of  claim 1 , wherein the applying the high flow-rate aspiration from the second pump to the aspiration port of the probe and the discontinuing the high flow-rate aspiration and reapplying the low flow-rate aspiration to the aspiration port of the probe is automatic. 
     
     
       3. The method of  claim 1 , wherein detecting that the aspiration port of the probe is insufficiently occluded comprises detecting a flow-rate increase at the probe for a predetermined amount of time. 
     
     
       4. The method of  claim 1 , wherein the first pump comprises a peristaltic pump and the second pump comprises a venturi pump. 
     
     
       5. The method of  claim 1 , wherein a transitional flow-rate aspiration between the low flow-rate aspiration and the high flow-rate aspiration is constantly increasing. 
     
     
       6. The method of  claim 1 , wherein the detecting comprises using a flow sensor, a vacuum sensor, or both. 
     
     
       7. The method of  claim 1 , wherein the first pump comprises a venturi pump and the second pump comprises a peristaltic pump. 
     
     
       8. A method for removing tissue from within an eye, comprising:
 aspirating fluid and material using a probe within the eye by pumping the fluid and material through an aspiration pathway with a first pump; 
 generating a command signal by detecting insufficient occlusion of the aspiration pathway during the pumping of the fluid and the material with the first pump; 
 aspirating material from within the eye using a second pump at the probe in response to the command signal; 
 reducing a flow-rate of the aspirating material to match an irrigation flow-rate on a condition that the flow-rate of the aspirating material exceeds the irrigation flow-rate; 
 not energizing the probe with ultrasound energy, in response to the command signal; 
 
       detecting an occlusion of the aspiration pathway;
 resuming aspiration of the material and the fluid with the first pump based on detecting the occlusion; and 
 energizing the probe with ultrasound energy based on detecting the occlusion. 
 
     
     
       9. The method of  claim 8 , wherein the second pump is applied for a predetermined time in response to the command signal, and wherein the command signal is generated in response to a pressure differential along the aspiration pathway being less than a threshold. 
     
     
       10. The method of  claim 8 , wherein the first pump comprises a volumetric pump, and the second pump comprises a pressure pump. 
     
     
       11. The method of  claim 10 , wherein the volumetric pump is a peristaltic pump and the pressure pump is a venturi pump. 
     
     
       12. The method of  claim 8 , wherein the first pump comprises a pressure pump and the second pump comprises a volumetric pump. 
     
     
       13. The method of  claim 12 , wherein the volumetric pump is a peristaltic pump and the pressure pump is a venturi pump. 
     
     
       14. The method of  claim 8 , wherein the generating the command signal by detecting insufficient occlusion is in response to a detected change in flow rate. 
     
     
       15. The method of  claim 8 , wherein the generating the command signal by detecting insufficient occlusion is in response to a detected change in vacuum pressure. 
     
     
       16. A method for applying aspiration to a probe, comprising:
 applying a low flow-rate aspiration from a first pump to an aspiration port of the probe; 
 applying ultrasonic energy to the probe; 
 receiving a user input to change to a high flow-rate aspiration from a second pump to increase occlusion at the aspiration port of the probe; 
 reducing the high flow-rate aspiration to match an irrigation flow-rate on a condition that the high flow-rate aspiration exceeds the irrigation flow-rate; 
 detecting that the aspiration port of the probe is insufficiently occluded; no longer applying ultrasonic energy to the probe, if the aspiration port of the probe is detected to be insufficiently occluded; and 
 switching the low flow-rate aspiration to the high flow-rate aspiration in response to the user input to increase occlusion at the aspiration port of the probe. 
 
     
     
       17. The method of  claim 16 , wherein a transitional flow-rate aspiration between the low flow-rate aspiration to the high flow-rate aspiration is constantly increasing. 
     
     
       18. The method of  claim 16 , wherein the first pump comprises a peristaltic pump and the second pump comprises a venturi pump. 
     
     
       19. The method of  claim 16 , wherein the first pump comprises a venturi pump and the second pump comprises a peristaltic pump. 
     
     
       20. A method for applying aspiration to a probe, the method comprising
 applying aspiration from a first pump to an aspiration port of the probe, wherein the first pump is a flow based pump; 
 energizing the probe with ultrasound energy; 
 detecting that the aspiration port of the probe is insufficiently occluded; 
 not energizing the probe with ultrasound energy, in response to detecting that the aspiration port of the probe is insufficiently occluded; and 
 applying aspiration from a second pump to the aspiration port of the probe to increase occlusion, in response to detecting that the aspiration port of the probe is insufficiently occluded; and 
 reducing a flow-rate of the aspiration from the second pump to match an irrigation flow-rate on a condition that the flow-rate of the aspiration exceeds the irrigation flow-rate; 
 wherein the second pump is a vacuum based pump and wherein the aspiration from the second pump is greater than the aspiration from the first pump. 
 
     
     
       21. The method of  claim 20 , wherein the flow based pump is a peristaltic pump and the vacuum based pump is a venturi pump.